Introduction: We assessed the effect of different available denture cleansers on the roughness and hardness of polyetherketoneketone, thermoinjection-molded polyamide, and polymethylmethacrylate. Materials and Methods: A total of 150 disc-shaped specimens were fabricated (10 mm × 2 mm) from these three denture base resins, and divided into five subgroups (n = 10) according to immersion procedures. One of these groups subjected to distilled water served as control, whereas other groups were subjected to daily cleansing with four denture cleansers (Corega, Protefix, Curaprox, and Perlodent) for 8 h a day for 140 days. The surface roughness and hardness values of specimens were recorded by measuring twice at baseline, and again after application of chemical solutions. Topography alterations after treatments were assessed with scanning electron microscopy. The data were subjected to statistical analysis and comparison among groups was done using Kruskal Wallis and Wilcoxon Signed Ranks tests. P-value <0.05 was considered significant. Results: The surface roughness of polyetherketoneketone, polymethylmethacrylate, and polyamide dentures was increased significantly by chemical solutions of denture cleansers. While the hardness value of polyetherketoneketone was not affected significantly after immersion in denture cleansers, those of polymethylmethacrylate and polyamide decreased significantly. Compared with Curaprox, the effervescent tablets significantly altered the surface hardness and roughness of polyamide. Conclusion: Denture cleansers can considerably alter the surface roughness and hardness of denture base resins and should be used carefully depending on the material.

The aim of this study was to evaluate the effect of sodium perborate effervescent tablets and citric acid solution on the color stability and surface topography of a new generation of high-performance polymer polyetherketoneketone (PEKK), thermoinjection-molded polyamide, and polymethylmethacrylate (PMMA). Fifty discshaped specimens were fabricated (10 mm × 2 mm) from PEKK (P group), polyamide (D group), and PMMA (M group). These groups were divided into five subgroups (n = 10) according to the storage media. The test groups were immersed in the following solutions: distilled water (Control), Corega, Protefix, Perlodent, and Curaprox. The color stability values (ΔE) were measured using a spectrophotometer before and after immersion in distilled water and four different denture cleansers for 8 hr/day for 140 days. Topography alterations after treatments were assessed with scanning electron microscopy (SEM). Data were analyzed by one-way analysis of variance (ANOVA) followed by Tukey's Honest Significant Difference test. The p < .05 was considered significant. All denture cleansers increased the ΔE values relative to the baseline values in the M, D, and P groups (p < .05). The Perlodent denture cleanser demonstrated the highest ΔE value in all groups, which was unacceptable. Curaprox denture cleanser showed the lowest ΔE value in the M and D groups (p < .05). Curaprox in all groups showed a ΔE value less than 3.7. For patients who have PEKKand polyamide-based prosthesis, the use of citric acid-based cleansers may be more recommended than sodium perborate-containing cleansers because of its clinically acceptable color changes on polymers in terms of color stability.

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We would like to remind physicians to be aware of peripheral malformations as signs of skeletal dysplasias and to consider acrodysostosis in the differential diagnosis. Although it is a rare condition, if diagnosed early, possible complications can be treated and outcomes may be improved.

Objective: The shear bond strength (SBS) of composite resin cement and color change to enamel bleached with two different concentrations of hydrogen peroxide (HP) bleaching agents in combination with two different laser applications was evaluated. Materials and Methods: The Er: YAG laser ( λ = 2940 nm) and diode laser ( λ = 940 nm) were used with the bleaching agent consisting of 40% HP opalescence (Opalescence Xtra Boost, Ulgen, South Jordan, UT, USA) and 35% HP whiteness (Whiteness HP Blue, FGM Dental Products, Joinville, SC, Brazil). Seventy-two human extracted teeth were randomly divided into two groups: For the 40% HP treatment, 36 specimens were divided into three subgroups: (1) HP agent with no laser treatment, (2) HP agent treated with Er: YAG laser, and (3) HP agent treated with diode laser. The same protocol was performed for the 35% HP. The color change was analyzed using the Commission Internationale de l’ Eclairage (CIE) L* a* b* system and surface roughness was analyzed by an atomic force microscope. The specimens were bonded with resin cement and a shear bond test was performed at 0.5 mm/min. The failure surfaces were evaluated using scanning electron microscope analysis. Results: Δ E value of the 40% HP + Er: YAG group was significantly higher than the other groups while diode groups showed the lower SBS values than the control groups ( p < 0.05). Conclusions: The Er: YAG laser with 40% HP may be effective for the brighter teeth and the use of Er: YAG laser produced higher adhesion between enamel and resin cement than diode laser.